[QUESTION] "Changes you made may not be saved." alert popup is displayed

I guess the alert still shows up even if you have storage set up. Add this to your initialization:

var editor = grapesjs.init({
   //...
   // Show an alert before unload the page with unsaved changes
   noticeOnUnload: 0,
   //...
})

By default it's set to true

It's probably because you have no storage set up

I thought about storage as well and was about to set up a dummy storage, hoping it would circumvent the problem. The noticeOnUnload: 0 works like a charm though, so no need for that.

Thank you very much.